Steering care

What is a rack and pinion and what it does? A rack and pinion consists of several parts and seals that allow one to turn the steering wheel at low speeds and when stopped, along with an assistance from driving. The parts that play a role in turning the vehicle are noted below. A steering shaft is attached to the steering column. The steering shaft has a pinion attached which attaches to a linear gear with teeth called the rack. When the steering wheel is rotated, the gear on the shaft turns onto the rack and allows it to grip onto the teeth of the rack, which then turns the wheels. Tie rods, which help push and pull the wheels when turning, are attached to the steering rack at each end. The system is fluid driven by the power steering pump. The power steering pump forces high pressure onto the steering hose, which connects to the rack and distributes fluid to help with lubrication for the moving components.

How does it break? There are several reasons why the rack and pinion fail. The first reason is that if there are tears and punctures on the seals attached to the steering rack, the system will not produce the same fluid pressure which will consequently cause fluid leaks, loose steering and/or hard steering. Seals can be replaced, depending on the make and model. A second reason is a lack of maintenance. Depending on the manufacture, intervals of fluid exchange or flushes are highly recommended. Fluids can become contaminated, making it difficult for the fluid to transfer through hoses, which in turn causes the system to work harder, in a similar manner to clogged arteries in our bodies. When the fluid doesn’t flow properly, the system will eventually fail. When contamination occurs, a replacement of the rack, pinion, and even the power steering pump may be needed. A third reason is a failure of the power steering pump. Lastly, normal wear and tear can cause the rack and pinion to break.

How do I know it needs to be replaced? Several signs will occur when the steering rack needs to be replaced. One of the signs is a whining noise when turning at a standstill. Another sign is difficulty with steering at lower speeds. When driving on the highway, loose steering and shaking on the steering wheel are signs of a bad rack. Badly worn tires are another sign. Lastly, a noticeable fluid leak (power steering fluid) is also a sign of replacement.

How much does it cost and why? Replacement of a steering rack can be a bit costly. The main reason for this is that often, you must replace multiple parts of the steering rack and pinion components because individual parts cannot be replaced. For example, the power steering fluid flush is needed along with a 4-wheel alignment to prevent wear and to fix alignment. Additionally, labour costs too matter as labour is intense and can take as long as five hours with two experienced technicians. Generally, the technician will recommend original manufactured parts replacements to ensure a good fit, better parts and labour warranty. When finance is a key element of concern, an aftermarket rack will get the job done with a limited warranty option.

What happens if I don’t replace it? If a bad rack and pinion isn’t replaced, your steering will be compromised, which is extremely dangerous.

Is it different on any car? On all the newest models, all rack and pinions are the same. On older cars and newer heavy-duty trucks, a steering box is used which is a re-circulating ball system, also known as a gear box.

Can I replace them by myself, or is there something else I can replace it with? It is highly recommended to have a professional technician or mechanic perform the replacement if you don’t have mechanical experience or have never replaced a rack and pinion in the past. Unfortunately, there are not any other alternative repairs for a bad rack and pinion. Proper tools, skills and knowledge are necessary.

What is a way to make it cost less? The only safe and cheap option would be to use an aftermarket or OEM rack and pinion. If an aftermarket rack and pinion is not within your budget, a tokunbo or used or salvaged yard parts may suffice, but safety can be a big concern.

NB: Parts of this piece are culled from the Internet.

Feedback

I drive a Toyota Camry 2007 model. The brake pedal is loose and soft, taking an extra effort for the car to stop whenever it is matched. I was advised twice to drain the brake fluid and replace it and I did that. The braking improved significantly and returned to its normal state later. Yet after a week or so, the brake became soft and loose again. Also, is it advisable to flush a car engine if there is sludge build up in it? Dayo

If there is no obvious and visible leakage on the brake system then the problem has to do with the brake master cylinder. Replacing the brake master cylinder will solve the problem.

Yes, you can flush the engine if there is sludge present in it. But it has to be done by a professional.

I need information about my Toyota Camry car popularly called orobo. I don’t know its year of manufacture. It swerves off the road slightly when I drive. I have done alignment several times and changed the ball joints and arms without solution. Please, sir what could be the problem? Denis

I believe the inner and outer tie rod ends also need to be replaced. Also, if the rack and pinion rubber bushings are worn you could also be experiencing the same problem.

My Nissan Pathfinder 3.5 refuses to accelerate. Is there a solution? Anonymous

Yes there is a solution, but you have to run a scan on the powertrain system of the vehicle first. The result of the scan is what will guide on what to do.

Generic codes

P0540: Intake air heater ‘A’ circuit

The engine control module uses an intake air heater to warm the incoming air for proper cylinder combustion. The ECM grounds the control coil of the IAH relay to energise the heater during cold operation. The control module will command the IAH ON when the engine coolant temperature is below 40 C (104 F). The power to the IAH heater is supplied by the battery positive voltage circuit through the IAH relay.

Possible causes

Faulty intake air heater relay

Faulty intake air heater

Intake air heater relay harness is open or shorted

Intake air heater relay circuit poor electrical connection

Intake air heater harness is open or shorted

Intake air heater circuit poor electrical connection

P0541: Intake air heater ‘A’ circuit low

The engine control module uses an intake air heater to warm the incoming air for proper cylinder combustion. The ECM grounds the control coil of the IAH relay to energise the heater during cold operation. The control module will command the IAH ON when the engine coolant temperature is below 40 C (104 F). The power to the IAH heater is supplied by the battery positive voltage circuit through the IAH relay.

NOTE: The code is detected when the engine control module (ECM) sends a bias voltage on diagnostic circuits one and two. If this voltage is not pulled low when the relay is OFF DTC P0541 will set. The ECM will only store info on first failure, it triggers the SES light on the second failure.

Possible causes

Faulty intake air heater relay

Faulty intake air heater

Intake air heater relay harness is open or shorted

Intake air heater relay circuit poor electrical connection

Intake air heater harness is open or shorted

Intake air heater circuit poor electrical connection

P0542: Intake air heater ‘A’ circuit high

The engine control module uses an intake air heater to warm the incoming air for proper cylinder combustion. The ECM grounds the control coil of the IAH relay to energise the heater during cold operation. The control module will command the IAH ON when the engine coolant temperature is below 40 C (104 F). The power to the IAH heater is supplied by the battery positive voltage circuit through the IAH relay.

NOTE: The code is detected when the engine control module sends a bias voltage on diagnostic circuits one and two. If this voltage is high with the relay ON, DTC P0542 will set. The ECM will only store info on first failure, it triggers the SES light on the second failure.

Possible causes

Faulty intake air heater relay

Faulty intake air heater

Intake air heater relay harness is open or shorted

Intake air heater relay circuit poor electrical connection

Intake air heater harness is open or shorted

Intake air heater circuit poor electrical connection

P0543: Intake air heater ‘A’ circuit open

The engine control module uses an intake air heater to warm the incoming air for proper cylinder combustion. The ECM grounds the control coil of the IAH relay to energise the heater during cold operation. The control module will command the IAH ON when the engine coolant temperature is below 40 C (104 F). The power to the IAH heater is supplied by the battery positive voltage circuit through the IAH relay.

NOTE: The code is detected when The engine control module sends a bias voltage on diagnostic circuits one and two. If this voltage is not pulled low when the relay is OFF, or is high with the relay ON, DTC P0543 will set. The ECM will only store info on first failure, it triggers the SES light on the second failure.

Possible causes

Faulty intake air heater relay

Faulty intake air heater

Intake air heater relay harness is open or shorted

Intake air heater relay circuit poor electrical connection

Intake air heater harness is open or shorted

Intake air heater circuit poor electrical connection

P0544: Exhaust gas temperature sensor circuit bank 1 sensor 1

The powertrain control module continuously monitors the exhaust gas temperature sensor for proper circuit continuity and out of range high values. The EGTS is located in front of the diesel oxidation catalyst and/or in front of the diesel particulate filter. The EGTS detects exhaust gas temperature and converts it into a voltage and feeds back to the PCM with the voltage signal in order to control engine conditions to effectively reduce emissions. The PCM sets the P0544 OBDII code when the exhaust gas temperature sensor is out of factory specifications.

The powertrain control module continuously monitors the exhaust gas temperature sensor for proper circuit continuity and out of range high values. The EGTS is located in front of the diesel oxidation catalyst and/or in front of the diesel particulate filter. The EGTS detects exhaust gas temperature and converts it into a voltage and feeds back to the PCM with the voltage signal in order to control engine conditions to effectively reduce emissions. The PCM sets the P0545 OBDII code when the exhaust gas temperature sensor is out of factory specifications.

The powertrain control module continuously monitors the exhaust gas temperature sensor for proper circuit continuity and out of range high values. The EGTS is located in front of the diesel oxidation catalyst and/or in front of the diesel particulate filter. The EGTS detects exhaust gas temperature and converts it into a voltage and feeds back to the PCM with the voltage signal in order to control engine conditions to effectively reduce emissions. The PCM sets the P0546 OBDII code when the exhaust gas temperature sensor is out of factory specifications.

The powertrain control module continuously monitors the exhaust gas temperature sensor for proper circuit continuity and out of range high values. The EGTS is located in front of the diesel oxidation catalyst and/or in front of the diesel particulate filter. The EGTS detects exhaust gas temperature and converts it into a voltage and feeds back to the PCM with the voltage signal in order to control engine conditions to effectively reduce emissions. The PCM sets the P0547 OBDII code when the exhaust gas temperature sensor is out of factory specifications.

The powertrain control module continuously monitors the exhaust gas temperature sensor for proper circuit continuity and out of range high values. The EGTS is located in front of the diesel oxidation catalyst and/or in front of the diesel particulate filter. The EGTS detects exhaust gas temperature and converts it into a voltage and feeds back to the PCM with the voltage signal in order to control engine conditions to effectively reduce emissions. The PCM sets the P0548 OBDII code when the exhaust gas temperature sensor is out of factory specifications.

The powertrain control module continuously monitors the Exhaust gas temperature sensor for proper circuit continuity and out of range high values. The EGTS is located in front of the diesel oxidation catalyst and/or in front of the diesel particulate filter. The EGTS detects exhaust gas temperature and converts it into a voltage and feeds back to the PCM with the voltage signal in order to control engine conditions to effectively reduce emissions. The PCM sets the P0549 OBDII code when the exhaust gas temperature sensor is out of factory specifications.

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